在NSString或nsmutablestring中不可能有多种颜色。我听说过一点NSAttributedString,它是在iPad SDK 3.2(或大约3.2)中引入的,并且在iPhone SDK 4.0 beta版中可用。

我想要一根有三种颜色的绳子。

我不使用3个独立的NSString的原因,是因为三个NSAttributedString子字符串的长度经常改变,所以我宁愿,不使用任何计算重新定位3个独立的NSString对象。

如果使用NSAttributedString是可能的,我怎么做以下-(如果不可能使用NSAttributedString,你会怎么做):

编辑: 记住,@"first", @"second"和@"third"随时会被其他字符串替换。所以使用硬编码的NSRange值是行不通的。


当前回答

斯威夫特4

let combination = NSMutableAttributedString()

var part1 = NSMutableAttributedString()
var part2 = NSMutableAttributedString()
var part3 = NSMutableAttributedString()

let attrRegular = [NSAttributedStringKey.font : UIFont(name: "Palatino-Roman", size: 15)]

let attrBold:Dictionary = [NSAttributedStringKey.font : UIFont(name: "Raleway-SemiBold", size: 15)]

let attrBoldWithColor: Dictionary = [NSAttributedStringKey.font : UIFont(name: "Raleway-SemiBold", size: 15),
                                 NSAttributedStringKey.foregroundColor: UIColor.red]

if let regular = attrRegular as? [NSAttributedStringKey : NSObject]{
    part1 = NSMutableAttributedString(string: "first", attributes: regular)

}
if let bold = attrRegular as? [NSAttributedStringKey : NSObject]{
    part2 = NSMutableAttributedString(string: "second", attributes: bold)
}

if let boldWithColor = attrBoldWithColor as? [NSAttributedStringKey : NSObject]{
    part3 = NSMutableAttributedString(string: "third", attributes: boldWithColor)
}

combination.append(part1)
combination.append(part2)
combination.append(part3)

属性列表请参见这里的NSAttributedStringKey在苹果文档

其他回答

斯威夫特4

let combination = NSMutableAttributedString()

var part1 = NSMutableAttributedString()
var part2 = NSMutableAttributedString()
var part3 = NSMutableAttributedString()

let attrRegular = [NSAttributedStringKey.font : UIFont(name: "Palatino-Roman", size: 15)]

let attrBold:Dictionary = [NSAttributedStringKey.font : UIFont(name: "Raleway-SemiBold", size: 15)]

let attrBoldWithColor: Dictionary = [NSAttributedStringKey.font : UIFont(name: "Raleway-SemiBold", size: 15),
                                 NSAttributedStringKey.foregroundColor: UIColor.red]

if let regular = attrRegular as? [NSAttributedStringKey : NSObject]{
    part1 = NSMutableAttributedString(string: "first", attributes: regular)

}
if let bold = attrRegular as? [NSAttributedStringKey : NSObject]{
    part2 = NSMutableAttributedString(string: "second", attributes: bold)
}

if let boldWithColor = attrBoldWithColor as? [NSAttributedStringKey : NSObject]{
    part3 = NSMutableAttributedString(string: "third", attributes: boldWithColor)
}

combination.append(part1)
combination.append(part2)
combination.append(part3)

属性列表请参见这里的NSAttributedStringKey在苹果文档

我写了helper来方便地添加属性:

- (void)addColor:(UIColor *)color substring:(NSString *)substring;
- (void)addBackgroundColor:(UIColor *)color substring:(NSString *)substring;
- (void)addUnderlineForSubstring:(NSString *)substring;
- (void)addStrikeThrough:(int)thickness substring:(NSString *)substring;
- (void)addShadowColor:(UIColor *)color width:(int)width height:(int)height radius:(int)radius substring:(NSString *)substring;
- (void)addFontWithName:(NSString *)fontName size:(int)fontSize substring:(NSString *)substring;
- (void)addAlignment:(NSTextAlignment)alignment substring:(NSString *)substring;
- (void)addColorToRussianText:(UIColor *)color;
- (void)addStrokeColor:(UIColor *)color thickness:(int)thickness substring:(NSString *)substring;
- (void)addVerticalGlyph:(BOOL)glyph substring:(NSString *)substring;

https://github.com/shmidt/MASAttributes

你也可以通过CocoaPods安装:pod 'MASAttributes', '~> 1.0.0'

我总是发现使用带属性的字符串是一个令人难以置信的漫长而乏味的过程。

所以我做了一个Mac应用程序,为你创建所有的代码。

https://itunes.apple.com/us/app/attributed-string-creator/id730928349?mt=12

这个方法非常简单。

let text = "This is a colorful attributed string"
let attributedText = 
NSMutableAttributedString.getAttributedString(fromString: text)
attributedText.apply(color: .red, subString: "This")
//Apply yellow color on range
attributedText.apply(color: .yellow, onRange: NSMakeRange(5, 4))

更多详情请点击这里; https://github.com/iOSTechHub/AttributedString

自iOS 7以来,你可以使用NSAttributedString与HTML语法:

NSURL *htmlString = [[NSBundle mainBundle]  URLForResource: @"string"     withExtension:@"html"];
NSAttributedString *stringWithHTMLAttributes = [[NSAttributedString alloc] initWithFileURL:htmlString
                                                                                       options:@{NSDocumentTypeDocumentAttribute:NSHTMLTextDocumentType}
                                                                            documentAttributes:nil
                                                                                         error:nil];
textView.attributedText = stringWithHTMLAttributes;// you can use a label also

你必须添加文件"string.html"到你的项目中,html的内容可以是这样的:

<html>
  <head>
    <style type="text/css">
      body {
        font-size: 15px;
        font-family: Avenir, Arial, sans-serif;
      }
      .red {
        color: red;
      }
      .green {
        color: green;
      }
      .blue {
        color: blue;
      }
    </style>
  </head>
  <body>
    <span class="red">first</span><span class="green">second</span><span class="blue">third</span>
  </body>
</html>  

现在,你可以使用NSAttributedString作为你想要的,即使没有HTML文件,例如:

//At the top of your .m file
#define RED_OCCURENCE -red_occurence-
#define GREEN_OCCURENCE -green_occurence-
#define BLUE_OCCURENCE -blue_occurence-
#define HTML_TEMPLATE @"<span style=\"color:red\">-red_occurence-</span><span style=\"color:green\">-green_occurence-</span><span style=\"color:blue\">-blue_occurence-</span></body></html>"

//Where you need to use your attributed string
NSString *string = [HTML_TEMPLATE stringByReplacingOccurrencesOfString:RED_OCCURENCE withString:@"first"] ;
string = [string stringByReplacingOccurrencesOfString:GREEN_OCCURENCE   withString:@"second"];
string = [string stringByReplacingOccurrencesOfString:BLUE_OCCURENCE    withString:@"third"];

NSData* cData = [string dataUsingEncoding:NSUTF8StringEncoding];

NSAttributedString *stringWithHTMLAttributes = [[NSAttributedString alloc] initWithData:cData
                                                                                options:@{NSDocumentTypeDocumentAttribute:NSHTMLTextDocumentType}
                                                                        documentAttributes:nil
                                                                                     error:nil];
textView.attributedText = stringWithHTMLAttributes;